Behaviour and ecology

Neocrinus decorus has mucus-covered tube feet on the pinnae of its arms which extend into the water and catch plankton.

Trophic strategy

Neocrinus decorus:

is a bottom-dwelling (epibenthic) filter feeder

feeds mainly on plankton

avoids coprophagae (eating its own faeces)

Behaviour

Neocrinus decorus is semi-sessile. It lives on the sea floor, mainly on hard substrates such as rocky outcrops, but doesn’t attach itself.

Like other crinoids, Neocrinus catches plankton by arranging its crown of arms into a parabolic fan and positioning this within a current. To process plankton more effectively, it faces the fan into the current.

The arms bear numerous rows of pinnules from which mucus covered tube feet extend and catch plankton. Food particles are passed down the arms and into the mouth.

The animal’s stem holds the arms off the sea floor, helping to position them where the currents are usually strongest. The stem also enables Neocrinus to reach plankton its rivals cannot.

Migration

This crinoid is not known to migrate however individuals are capable of crawling to better feeding areas by using their arms for 'rapid' movement or cirri for slow movement.